With the approach of the U.N. deadline for Iraq to release Kuwait suddenly measured in hours, bids for peace were drowned out Tuesday by rumblings of war.

As the clock ticked toward a deadline Tuesday of midnight EST for Iraq to withdraw from the emirate or face possible attack, the mood in Washington was grim and the message one of resolve.President Bush was briefed early Tuesday by his intelligence and national security advisers. Late Monday, he signed the congressional resolution, passed over the weekend, authorizing him to use military force to drive Saddam Hussein from Kuwait.

Bush walked the grounds of the White House Tuesday at dawn "just to reflect on the day," spokesman Marlin Fitzwater said.

Kuwait's government-in-exile said "the hour of liberation is near." The Kuwaiti ambassador to Syria, Ahmed Abdul-Aziz al-Jassem, said Saddam bore full responsibility if there was war.

The U.N. Security Council met Tuesday to work on a final peace offer that would guarantee that Iraq would not be attacked if it pulls out.

"We will be talking about and supporting a final appeal to Sad-dam Hussein," the British ambassador, Sir David Hannay, said as he entered the Security Council chambers. "I believe that a number support the idea of a largely political appeal."

"A last-minute appeal is very good, and we're going to support it," said the Soviet U.N. ambassador, Yuli Vorontsov, as he entered the Security Council chambers.

However, neither Britain nor the Soviet Union endorsed a French plan, which offers a Middle East peace conference so Saddam would not fully lose face. That provision was unacceptable to the Americans.

"We don't believe it's the appropriate time or the appropriate circumstances to present such a statement, certainly with the linkage that's involved in the text," U.S. Ambassador Thomas R. Pickering told reporters.

Supporters of the French plan included Italy and Germany.

Belgium, meanwhile, proposed that U.N. Secretary-General Javier Perez de Cuellar appoint a mediator to lay the groundwork for a Middle East peace conference.

Iranian President Hashemi Rafsanjani said the Tehran government was in touch with a number of unidentified countries in last-minute efforts to avert a war, the Islamic Republic News Agency reported Tuesday. It gave no details.

The U.S. State Department Tuesday advised Americans to leave Pakistan and Sudan because of what it called unstable conditions due to Iraq's refusal to leave Kuwait.

U.S. personnel not considered essential and all dependents have been ordered out.

Iraq's air force commander was quoted Tuesday as saying pilots trained for suicide missions were ready for the "mother of battles."

Al-Thawra, newspaper of Iraq's ruling Baath party, said in a front-page editorial Tuesday that Kuwait is under Iraq and "will remain so forever."

"It is Bush who wanted the war," said the army daily, Al-Qaddissiya. "But let him know that the furnace of hell will be open to the Americans and to their allies when they come."

In London, 28 Iraqi diplomats ordered to leave Britain flew out of Heathrow airport with their families Tuesday. Some in the 75-member party chanted "Long live Saddam!" and other slogans as they were escorted to a Royal Jordanian Airlines flight to Amman, Jordan.

War preparations and protests intensified as the deadline loomed.

Across the gulf region, people fearing an Iraqi chemical attack sealed their homes. Turks streamed away from the Iraqi frontier, and the last flights out of the region before Tuesday's deadline left with few empty seats.

Security alerts were posted at airports throughout the world and extraordinary precautions taken from the Middle East to the United States, which ordered all non-essential diplomats out of the Middle East.

"No blood for oil!" was chanted at anti-war protests across the United States, including one by 5,000 people in front of the White House.

In Israel - which Saddam has called a primary target for attack - up to 20,000 Jews prayed at Jerusalem's Western Wall holy site.

"Who doesn't shiver as the war drums are heard?" an Israeli political party said in its call to prayer.

Some Pentagon and administration officials have privately predicted that Bush would wait for several days after the deadline to give Saddam an opportunity to boast he defied the deadline.

But the White House said Monday that Iraq would be "on borrowed time" after the midnight deadline, when the United Nations has ordered Iraq to end its occupation of Kuwait or face the likelihood of an attack by the U.S.-led multinational coalition arrayed against it.

Military officials have suggested a night strike is preferred because of the West's more sophisticated aircraft and night-vision technology. Also, a new moon comes tonight and it will grow brighter each night until the end of the month.

In Iraq, Lt. Gen. Muzahim Saab Hassan sent a message to Saddam on Monday saying air force suicide units were ready to hit "targets in the air, on land and at sea," according to the official Iraqi News Agency.

"They all are ready for the great jihad (holy war) and for sacrifice," INA quoted the general as saying. It was the first Iraqi mention of such units.